thats right switches like rat, ditching pb, idg pb etc...
But for some reason(which is what i am trying to find out) B hyd pump sw is also guarded while the G & Y are not.
is it the proximity to the fuel x-feed which is right above it?
speculating is not some thing I am comfortable with:*

As I wrote earlier, if you mistakenly sw off the B, you will lose the B hyd sys immediately. You can, of course, switch it on again if you want. If you switch off the G or Y pump sw, you will not lose either sys because the PTU will backup (provided there is fluid). So, guard the sw to pause and ensure you really want to switch it off.

Blue Pump Override
 

There are 2 blue pump switches. The one in the HYD overhead panel will turn off the blue pump, even in flight and no the RAT will not deploy! This switch is not guarded!

Blue Pump override in Maint panel (Guarded)

As it's name suggests if you push this the Blue pump will be activated, where it would not be normally - So on the ground without engines running setting the blue pump to OVERRIDE will power up blue HYD and then things like FLAPS/SLATS, FLIGHT CONTROLS all become powered and able to move and create damage if not kill. Setting this to off, will turn off the pump if both your engines are off and you are on the ground.

This is why the yellow electric pump is also guarded! You are simply powering the flight controls and SLAT/FLAPS creating danger, which should be assessed from outside the aircraft before powering these systems.

Hence the call on interphone "Confirm clear to pressurize?"

Sorry but:
http://www.!!!!!!!!!!!!!!/open.file/1063035/L

Yellow pump guarded
 

Yes you are right. The yellow electric pump is not guarded, however I have the latest FCOM which indicates it is! Will have another look at work tomorrow! By the way the blue pump control on the HYD panel is guarded see your own referred picture!
Oh well, I maintain the blue pump override located onthe maint panel is guarded due to the possible powering of Flight controls etc on the ground.
Unfortunately this does raise the question of the guard on the blue pump PB located on the HYD panel. I know for a fact you can turn that on and off and you only loose the blue system. Not a biggy unless you were already down one HYD system.
The effects of turning it off are fully recovered by turning back on - so why the guard on this one? I think I will go with fantom's idea!

Again I know nothing about A320's. Is the panel in the picture considered a maintenance panel? It looks a lot loke the pilots overhead panels I have seen on many other aircraft. Shouldn't a maintenance panel be somewhere where maintenance personal can get to it, not the flight crew.

Here is the maintenance panel:
http://www.meriweather.com/320/aft/maint.html

Where is this panel located, not in the flight station I assume?

In the Cockpit:
http://img242.imageshack.us/img242/1148/50vuiu1.th.jpg

To tell it in words, the maintenance panel is on the overhed panel but it's far up. Out of easy reach for pilots when they are sitting down in their seats.
And as for the yellow electric pump switch, at least on our planes it's not guarded.
I think the last 320 series plane was delivered around september 04 with a serial 2200 and something.